KVM: selftests: Rename timespec_diff_now to timespec_elapsed

In response to some earlier comments from Peter Xu, rename
timespec_diff_now to the much more sensible timespec_elapsed.

No functional change intended.
Reviewed-by: Jacob Xu <jacobhxu@google.com>
Reviewed-by: Makarand Sonare <makarandsonare@google.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20210112214253.463999-2-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

tools/testing/selftests/kvm/demand_paging_test.c

@@ -64,7 +64,7 @@ static void *vcpu_worker(void *data)
 			    exit_reason_str(run->exit_reason));
 	}
 
-	ts_diff = timespec_diff_now(start);
+	ts_diff = timespec_elapsed(start);
 	PER_VCPU_DEBUG("vCPU %d execution time: %ld.%.9lds\n", vcpu_id,
 		       ts_diff.tv_sec, ts_diff.tv_nsec);
 
@@ -95,7 +95,7 @@ static int handle_uffd_page_request(int uffd, uint64_t addr)
 		return r;
 	}
 
-	ts_diff = timespec_diff_now(start);
+	ts_diff = timespec_elapsed(start);
 
 	PER_PAGE_DEBUG("UFFDIO_COPY %d \t%ld ns\n", tid,
 		       timespec_to_ns(ts_diff));
@@ -190,7 +190,7 @@ static void *uffd_handler_thread_fn(void *arg)
 		pages++;
 	}
 
-	ts_diff = timespec_diff_now(start);
+	ts_diff = timespec_elapsed(start);
 	PER_VCPU_DEBUG("userfaulted %ld pages over %ld.%.9lds. (%f/sec)\n",
 		       pages, ts_diff.tv_sec, ts_diff.tv_nsec,
 		       pages / ((double)ts_diff.tv_sec + (double)ts_diff.tv_nsec / 100000000.0));
@@ -339,7 +339,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 		PER_VCPU_DEBUG("Joined thread for vCPU %d\n", vcpu_id);
 	}
 
-	ts_diff = timespec_diff_now(start);
+	ts_diff = timespec_elapsed(start);
 
 	pr_info("All vCPU threads joined\n");
 

tools/testing/selftests/kvm/dirty_log_perf_test.c

@@ -52,7 +52,7 @@ static void *vcpu_worker(void *data)
 
 		clock_gettime(CLOCK_MONOTONIC, &start);
 		ret = _vcpu_run(vm, vcpu_id);
-		ts_diff = timespec_diff_now(start);
+		ts_diff = timespec_elapsed(start);
 
 		TEST_ASSERT(ret == 0, "vcpu_run failed: %d\n", ret);
 		TEST_ASSERT(get_ucall(vm, vcpu_id, NULL) == UCALL_SYNC,
@@ -149,7 +149,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 		pr_debug("Waiting for vcpu_last_completed_iteration == %lu\n",
 			iteration);
 
-	ts_diff = timespec_diff_now(start);
+	ts_diff = timespec_elapsed(start);
 	pr_info("Populate memory time: %ld.%.9lds\n",
 		ts_diff.tv_sec, ts_diff.tv_nsec);
 
@@ -157,7 +157,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 	clock_gettime(CLOCK_MONOTONIC, &start);
 	vm_mem_region_set_flags(vm, PERF_TEST_MEM_SLOT_INDEX,
 				KVM_MEM_LOG_DIRTY_PAGES);
-	ts_diff = timespec_diff_now(start);
+	ts_diff = timespec_elapsed(start);
 	pr_info("Enabling dirty logging time: %ld.%.9lds\n\n",
 		ts_diff.tv_sec, ts_diff.tv_nsec);
 
@@ -176,7 +176,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 					 vcpu_id, iteration);
 		}
 
-		ts_diff = timespec_diff_now(start);
+		ts_diff = timespec_elapsed(start);
 		vcpu_dirty_total = timespec_add(vcpu_dirty_total, ts_diff);
 		pr_info("Iteration %lu dirty memory time: %ld.%.9lds\n",
 			iteration, ts_diff.tv_sec, ts_diff.tv_nsec);
@@ -184,7 +184,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 		clock_gettime(CLOCK_MONOTONIC, &start);
 		kvm_vm_get_dirty_log(vm, PERF_TEST_MEM_SLOT_INDEX, bmap);
 
-		ts_diff = timespec_diff_now(start);
+		ts_diff = timespec_elapsed(start);
 		get_dirty_log_total = timespec_add(get_dirty_log_total,
 						   ts_diff);
 		pr_info("Iteration %lu get dirty log time: %ld.%.9lds\n",
@@ -195,7 +195,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 			kvm_vm_clear_dirty_log(vm, PERF_TEST_MEM_SLOT_INDEX, bmap, 0,
 					       host_num_pages);
 
-			ts_diff = timespec_diff_now(start);
+			ts_diff = timespec_elapsed(start);
 			clear_dirty_log_total = timespec_add(clear_dirty_log_total,
 							     ts_diff);
 			pr_info("Iteration %lu clear dirty log time: %ld.%.9lds\n",
@@ -211,7 +211,7 @@ static void run_test(enum vm_guest_mode mode, void *arg)
 	/* Disable dirty logging */
 	clock_gettime(CLOCK_MONOTONIC, &start);
 	vm_mem_region_set_flags(vm, PERF_TEST_MEM_SLOT_INDEX, 0);
-	ts_diff = timespec_diff_now(start);
+	ts_diff = timespec_elapsed(start);
 	pr_info("Disabling dirty logging time: %ld.%.9lds\n",
 		ts_diff.tv_sec, ts_diff.tv_nsec);
 

tools/testing/selftests/kvm/include/test_util.h

@@ -64,7 +64,7 @@ int64_t timespec_to_ns(struct timespec ts);
 struct timespec timespec_add_ns(struct timespec ts, int64_t ns);
 struct timespec timespec_add(struct timespec ts1, struct timespec ts2);
 struct timespec timespec_sub(struct timespec ts1, struct timespec ts2);
-struct timespec timespec_diff_now(struct timespec start);
+struct timespec timespec_elapsed(struct timespec start);
 struct timespec timespec_div(struct timespec ts, int divisor);
 
 #endif /* SELFTEST_KVM_TEST_UTIL_H */

tools/testing/selftests/kvm/lib/test_util.c

@@ -84,7 +84,7 @@ struct timespec timespec_sub(struct timespec ts1, struct timespec ts2)
 	return timespec_add_ns((struct timespec){0}, ns1 - ns2);
 }
 
-struct timespec timespec_diff_now(struct timespec start)
+struct timespec timespec_elapsed(struct timespec start)
 {
 	struct timespec end;